genetics

Genetics as it applies to evolution, molecular biology, and medical aspects.

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Cris
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genetics

Post by Cris » Wed Sep 06, 2006 2:47 am

hi everybdy,
i have a ?, how many different DNA molecules 8 nucleotide pairs long are possible???
please help me

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mith
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Post by mith » Wed Sep 06, 2006 3:34 am

try writing them out and see if there's a pattern
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Enjoying one moment at a time;
Accepting hardships as the pathway to peace;
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Cris
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Post by Cris » Wed Sep 06, 2006 3:43 am

Thanks for helping me, but could you be a bit more specific, i still don’t understand how am i suppose to find the answer...

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Post by wbla3335 » Wed Sep 06, 2006 6:53 am

4X4X4X4X4X4X4X4=65536 for a single strand, as in a primer. Twice this number if you include the complementary antisense strand (each strand being a different molecule), but I suppose some of the complementary strands would be the same as some of the sense strands, so the actual number of different molecules would be less than 131,072. Anyone care to tackle this issue?

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canalon
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Post by canalon » Thu Sep 07, 2006 2:00 am

Multiplying by 2 does not make sense, since the antisense molecule is constrained by the sense one, there is only 4 choice for each pair so 4^8 is the answer.
Patrick

Science has proof without any certainty. Creationists have certainty without
any proof. (Ashley Montague)

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Post by wbla3335 » Thu Sep 07, 2006 6:40 am

Hi Canalon,

Yes, I see your point. ALL antisense strands will have an identical sense counterpart. This certainly makes things easier. So, 65536 it is.

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